For the IAS and the IPS, a candidate must be a citizen of India. For other services, a candidate must be either a citizen of India or a citizen of some other country (eligible after meeting with some special conditions).

A candidate must have attained the age of 21 years and must not have attained the age of 32 years on the 1st of August of examination year. The upper age-limit is relaxable, maximum of 5 years for SC/STs candidates and 3 years for OBC candidates. Age relaxation is also applicable for Ex-Defense personnel and candidates with certain disability.

A candidate must hold a Universities degree, or possess an equivalent qualification for appearing in Civil Services Examination. Candidates who have appeared in the final year of degree examination and also the candidates who intend to appear at such a qualifying examination will also be eligible for admission to the Preliminary Examination. But such candidates have to produce proof of passing the requisite examination before appearing in Civil Services (Main) Examination.